Sinker head



Patented May 4, 1954 UNITED STATS ATENT OFFICE SINKER HEAD Application March 26, 1951, Serial No. 217,507

4 Claims.

My invention is an improved sinker head for a full-fashioned knitting machine, and is designed to provide more accurate guidance of the jack sinkers and dividing sinkers between the needles and a more durable presser face for closing the beards of the needles when the latter are rocked and moved downward by the action of the needle bar.

m invention is further designed to facilitate th reconditioning of sinker heads which have become worn in use.

In the operation of full-fashioned knitting machines of the Cotton type, the yarn is measured and kinked around the needles by the movements of jack sinkers and dividing sinkers which slide in narrow slots in a brass sinker head having faces between the sinkers against which the needle beards are pressed and moved downward to close the beards before casting off a row of loops on the needles.

Such sinker heads wear rapidly under the friction and impacts incident to knitting, and particularly in the knitting of relatively coarse fabrics, such as sweater fabrics, on coarse gauge machines.

The replacement of a sinker head is relatively costly, and entails considerable economic waste since the major portion thereof may be still serviceable when it is required to be discarded due to the scoring of the presser edge.

In accordance with my invention the scoring of the presser edge and distortion of the sinker head is minimized by the provision of a replaceable hardened steel strip in a longitudinal slot extending transversely to and beneath the sinker slots in a ridge at the front of the sinker head by which the final guidance of the sinkers between the needles is effected. The steel strip may form only a portion of th thickness of the presser edge, but preferably the steel strip is provided with a slotted lip forming fingers lying in front of the brass partitions between the sinkers and forming a hardened steel presser edge for the needle beards. The strips are interlocked with the sinker head, but may be replaced when worn or damaged, thereby salvaging the unw-orn portions of the sinker head.

The principles of my invention and the best form in which I have contemplated applying such principles will more fully appear from the following description and the accompanying drawings in illustration thereof.

In the drawings Fig. 1 is a transverse sectional view of a sinker head embodying my improvements and having a needle bar and knock-over bar in juxtaposition thereto; Fig. 2 is a greatly magnified front elevation of a portion of the bottom of the sinker head intermediate the ends thereof; Fig. 3 is a greatly magnified detached transverse sectional view of the reinforcing strip shown in Figs. 1 and 2; Fig. 4 is a top plan view of the bottom of the sinker head with the sinkers removed; Fig. 5 is a. top plan view of the reinforcing strip detached from the bottom of the sinker head; Fig. 6 is a fragmentary front elevation of one end of the bottom of the sinker head shown in Figs. 4 and 5; Fig. '7 is a bottom view of an end of the bottom of the sinker head shown in Fig. 6 looking in the direction of the arrow I- E of Fig. 6; Fig. 8 is a greatly magnified fragmentary transverse sectional view taken on the line 88 of Fig. 6; Fig. 9 is a greatly magnified transverse sectional view similar to that shown in Fig. 8 but with the slotted lip omitted from the reinforcing strip; Fig. 10 is a fragmentary front elevation of the modified construction shown in Fig. 9 and Fig. 11 is a detached transverse sectional view of the reinforcing strip shown in Figs. 9 and 10.

In the drawings there is shown a sinker head assembly A mounted on the center bed B of the machine and in juxtaposition to the knock-over bits assembly C and the needle bar assembly D of 2. Cotton type full-fashioned knitting machine.

The sinker head comprises a bottom member I forming a bed having a ridge 2 along the forward edge thereof, and a lubricant wick trough 3 extending longitudinally parallel with the ridge 2. The bed and the ridge are provided with sinker slots 4 for the jack sinkers 5 and dividing sinkers 6 whose top edges are ngaged in slots 1 in the sinker cap 8. A verge plate 9 is mounted on the cap 8 to limit the forward stroke of the jack sinkers and dividing sinkers. The forward portion 10 of the lower surface of the bottom member I tapers upwardly toward the ridge 2 to provide room for the operation of the knock-over bit assembly C which has trunnions (not shown) journalled in the depending bearings E of the sinker head.

In accordance with my invention, a longitudinal slot I i is cut in the sinker bed transversely to and slightly beneath the sinker slots 3 in the ridge 2, and a beveled steel strip I2 is inserted in the slot H and secured therein by peening the forward edge of the bottom member 5 into shallow grooves l3 cut transversely in the bottom of the strip 12. The steel strip is thereby securely interlocked with the brass sinker head. Preferably the strip [2 is' provided with an upturned lip I4 ridge 2 so that th presser edge consists partly of brass and partly of steel.

The width of the slots 4 and 15 will of course vary with the gauge of the. machine, but ,it is preferable that the widthsof the slots [5 be slightly greater than the widths of the slots 4.

For instance, in a typical construction wherein the width of the slots 4 is .012" the widths of the slots I5 may approximate .016" and the-thick.- ness of the metal between the bottom of the slots 4randgthe top of the-striplt-mayapproximate, say, .005".

By constructing thesinker head as above de-.

scribed, wear and distortion are minimized,-, and should-the press edge become scored by the action-of the needle beards, the strip may -be- If the stripusedwas initially of the lipless type shown in Figs; 9 to 11 and the press edge of the ridge 2 ;become-scored,'the edge :maybe ground'offfor a sufficient distance-to permit the insertion in the slotll of a strip lZhaVinga:

replaced lip. l4 thereon forming a new .facefor the presser edge,

The steel strip 12 has a lower coefiicient of ex:

pansion than the brass ofthegsinker head and' tends to retard expansion or contraction of the ridge 2sothat the slots therein aremaintained in correct registrationwith the spacesibetween theneedles I! whichare mounted in a'journalled steelbar.

Having describedjm-y invention, I claim: 1. A sinker head bottom member comprising azrsoft metal bed'having a;ridge along its forward edge and containing sinker slots,- said bed'havingwa. lower surface tapering upward toward said ridge, said bed containing alongitudinal-slot transverse to and beneath the sinker slots of said ridge, and a hardened metallic strip secured in said slot and having a slotted lip extending upward along the edge of said ridge and forming fingers between said sinker slots and extending to substantially the top of said ridge.

2. A sinker head bottom member comprising a soft metal bed having sinker slots extending transversely thereto, said bed having a slot therein extending transversely to and lying beneath the forward ends of said sinker slots, and a steel strip seated in said longitudinal slot and having grooves therein containing portions of said bed extending beneath said strip to interlock said strip and bed:

3. A-sinkerhead bottom member comprising a soft, metal bed having sinker slots extending transversely thereto, said bed having a slot thereinextending transversely to and lying beneath the forward ends of said;sinker slots, and a steel strip seated in said longitudinal "slot and having a -slotted lip forming fingers between saidsinker slots and extending to substantially the top thereof, theslots in said lip being of greater width than the sinker slots of said bed.

4; Ina, full fashioned knittingmachine, a sinker headghavinga bottom member of soft metal and containing sinker slots; and a steel strip extending longitudinally of said member beneath said slots and having a slotted lip forming hard fingers shielding the edges of said member between-the slots therein, said strip having arlower coeflicient of expansion than ,saidmember.

References Cited in the file of this patent- UNITED STATES PATENTS Number Name Date 2,061,299 Cobert Nov. 1'7, 19 36 2,384,451 Brumbach Sept. 11, 1945 2,422,479 Golaszevvski et a1. June 17, 1947 FOREIGN PATENTS Number Country Date- 250 Great Britain of 1889 

